Increased use of mobile devices, such as smartphones and tablets, with an expanding number of wireless services offered on the devices, such as streaming video, have placed increased data loads and throughput requirements on wireless networks. To handle the increasing amount of wireless services to an increasing numbers of users, various multiple antenna techniques can be employed in wireless network environments to meet the increasing data and throughput demands.
In homogeneous networks, transmission stations, also called macro nodes, can provide basic wireless coverage to mobile devices. The geographical coverage area for each node can be referred to as a cell. The geographical coverage area of a macro node can be referred to as a macro cell. Heterogeneous networks (HetNets) were introduced to handle increased traffic loads on the macro nodes due to increased usage and functionality of mobile devices. HetNets can include a layer of planned high power macro nodes (or macro eNode Bs) overlaid with layers of lower power nodes (micro-nodes, pico-nodes, femto-nodes, home-nodes, relay stations, WLAN APs, integrated 3GPP pico with co-located WLAN APs, etc.) that can be deployed in a less organized or uncoordinated manner within the coverage area of the macro nodes. The macro nodes can be used for basic coverage, and the low power nodes can be used to fill coverage holes, to improve capacity in hot-zones or at the boundaries between the macro nodes' coverage areas, and to improve indoor coverage where building structures impede signal transmission.
However, even with a targeted deployment of lower power nodes, many users still receive a stronger downlink signal or have a greater downlink capacity from the tower-mounted macro node. For a more balanced use of nodes in a HetNet, such as to balance the traffic load for a given node, the use of node association and radio access technology (RAT) selection can be used to reduce the load on selected nodes such as macro-nodes. A reduced load on the nodes can provide users with better service.
Several approaches to node association and RAT selection have emerged for different embodiments of multiple radio access technology (multi-RAT) HetNet architectures to better distribute traffic across the overall network. Current methods for network selection between multi-radio networks (e.g. for WiFi offload between a third generation partnership project (3GPP) network and wireless local area network (WLAN) networks) rely on user equipment (UEs) to make network selection decisions. Mechanisms to guide UE network selection can be based on semi-static policies available from an access network discovery & selection function (ANDSF). Currently, many of the mechanisms to guide UE network selection rely on the UEs to account for local radio link conditions before making network selection decisions.
Reference will now be made to the exemplary embodiments illustrated, and specific language will be used herein to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended.